The Indians completed the trade for the switch-hitting Crisp after reports of the deal were reported Tuesday night. Crisp was not in the Athletics' starting lineup Tuesday and he left the Oakland clubhouse at Minute Maid Field in Houston about an hour before the start of the game.
Crisp, who will turn 37 in November, has just over $2 million left on his current contract that paid him $11 million this year.
Crisp has spent the entire 2016 season on Oakland's active roster, batting .235 with 24 doubles, four triples, 11 home runs and 47 RBIs in 102 games. He has scored 45 runs with seven stolen bases this year.
Crisp is hitting .345 with runners on base and is leading the major leagues with a .424 batting average with runners in scoring position. He has appeared in 58 games in left field and 36 games in center field for the A's.
Crisp owns a career average of .266 with 128 home runs and 631 RBIs across 15 seasons after debuting with the Indians in August 2002.
Crisp spent parts of four seasons with the Indians (2002-05), hitting .287 with 35 homers and 176 RBIs in 415 games finished tied for fifth in the American League with 42 doubles in 2005 prior to being traded to the Boston Red Sox that offseason.
Crisp has spent the last seven seasons in Oakland, where he hit a career-high 22 home runs in 2013 and tied for the AL lead in stolen bases (49) in 2011. He is currently 10th among active major league players with 306 steals.
Crisp has been involved in 31 postseason games across five seasons, hitting .282 with one home run and eight RBIs. He was a member of the 2007 world champion Red Sox.
Crisp is expected to report to the Indians on Thursday and will be placed on the active roster the following day.
The Indians signed Hynes to a minor league deal on Aug. 4 after he was released by the Toronto Blue Jays. He made one appearance at Triple-A Columbus before being sent to Double-A Akron.
The Indians lead the American League Central by 4 1/2 games entering Wednesday's action, and they lost outfielder Michael Brantley to season-ending right biceps surgery on Aug. 15. Brantley hadn't played since May 9.